Systems, methods, and devices for enhanced power saving for mobile terminated communication

ABSTRACT

A user equipment (UE) is configured to send a request to use an enhanced power saving mode (ePSM) to a mobility management entity (MME) of a mobile communications network. The UE is configured to receive configuration parameters from the MME including a time length for an idle mode and a time length for a power saving mode. The UE is configured to cycle between the idle mode and the power saving mode based on the power saving mode parameters, wherein the UE is available to receive transmissions during the idle mode and unavailable to receive transmissions during the power saving mode.

RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/746,681, filed Jun. 22, 2015, titled “SYSTEMS, METHODS, AND DEVICESFOR ENHANCED POWER SAVING FOR MOBILE TERMINATED COMMUNICATION,” whichclaims the benefit under 35 U.S.C. §119(e) of U.S. ProvisionalApplication No. 62/102,984, filed Jan. 13, 2015, titled “ENHANCED POWERSAVING MODE FOR EFFICIENT MOBILE TERMINATED COMMUNICATION” and U.S.Provisional Application No. 62/127,994, filed Mar. 4, 2015, titled“ENHANCED POWER SAVING MODE FOR EFFICIENT MOBILE TERMINATEDCOMMUNICATION,” all of which are hereby incorporated by reference hereinin their entirety.

TECHNICAL FIELD

The present disclosure relates to power saving on a mobile communicationdevice and more particularly relates to an enhanced power saving modefor efficient mobile terminated communication.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a communication system forproviding communication services to a wireless mobile device consistentwith embodiments disclosed herein.

FIG. 2 is a schematic block diagram illustrating a call flow for a powersaving mode.

FIG. 3 is a schematic block diagram illustrating an example call flowfor an enhanced power saving mode consistent with embodiments disclosedherein.

FIG. 4 is a schematic block diagram illustrating another example callflow for an enhanced power saving mode consistent with embodimentsdisclosed herein.

FIG. 5 is a schematic block diagram illustrating an example call flowfor forwarding enhanced power saving mode parameters to a servinggateway or a packet data network gateway consistent with embodimentsdisclosed herein.

FIG. 6 is a schematic block diagram illustrating an example call flowfor forwarding enhanced power saving mode parameters to a locationcenter consistent with embodiments disclosed herein.

FIG. 7 is a schematic block diagram illustrating components of a userequipment (UE) consistent with embodiments disclosed herein.

FIG. 8 is a schematic diagram of a mobile device consistent withembodiments disclosed herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Wireless mobile communication technology uses various standards andprotocols to transmit data between a base station and a wireless mobiledevice. Wireless communication system standards and protocols caninclude the 3rd Generation Partnership Project (3GPP) long termevolution (LTE); the Institute of Electrical and Electronics Engineers(IEEE) 802.16 standard, which is commonly known to industry groups asWiMAX (Worldwide Interoperability for Microwave Access); and the IEEE802.11 standard, which is commonly known to industry groups as WiFi. In3GPP radio access networks (RANs) in LTE systems, the base station canbe a combination of Evolved Universal Terrestrial Radio Access Network(E-UTRAN) Node Bs (also commonly denoted as evolved Node Bs, enhancedNode Bs, or eNodeBs) and Radio Network Controllers (RNCs) in an E-UTRAN,which communicates with the wireless mobile device, known as userequipment (UE). A downlink (DL) transmission can be a communication fromthe base station (or eNodeB) to the wireless mobile device (or UE), andan uplink (UL) transmission can be a communication from the wirelessmobile device to the base station.

The present disclosure proposes systems methods and devices to improvepower efficiency for mobile communication. Examples and embodimentsherein include proposed changes to 3GPP standards to improve powerefficiency for UE communication, such as machine type communication(MTC) devices or other devices, that require mobile terminated (MT)communication and which may also have some maximum delay deliveryrequirements. For example, some MT communications may have maximum delayrequirements of an hour, a half hour, 15 minutes, 10 minutes, fiveminutes, or less. Some embodiments disclosed herein may be directed tothe 3GPP Release 13 FS_HLComm in SA2 for Study on Optimizations toSupport High Latency Communications.

According to one embodiment, a UE is configured to send a request to usean enhanced power saving mode (ePSM) to a mobility management entity(MME) of a mobile communications network. The UE is configured toreceive configuration parameters from the MME including a time lengthfor an idle mode and a time length for a power saving mode and release aradio resource control (RRC) connection with the mobile communicationsnetwork. The UE is configured to cycle between the idle mode and thepower saving mode based on the power saving mode parameters, wherein theUE is available to receive transmissions during the idle mode andunavailable to receive transmissions during the power saving mode.

A detailed description of systems and methods consistent withembodiments of the present disclosure is provided below. While severalembodiments are described, it should be understood that disclosure isnot limited to any one embodiment, but instead encompasses numerousalternatives, modifications, and equivalents. In addition, whilenumerous specific details are set forth in the following description inorder to provide a thorough understanding of the embodiments disclosedherein, some embodiments can be practiced without some or all of thesedetails. Moreover, for the purpose of clarity, certain technicalmaterial that is known in the related art has not been described indetail in order to avoid unnecessarily obscuring the disclosure.

FIG. 1 illustrates an example communication system 100 for 3GPP access.The communication system 100 illustrates a variety of components thatmay be used to provide communication services or access to a UE 102. Thecommunication system 100 includes an E-UTRAN 104, which includes aplurality of eNBs 106. The communication system 100 also includes a corenetwork 108, for example, an evolved packet core (EPC) that includes anMME 110, a home subscriber server (HSS) 112, a serving gateway (SGW)114, a packet data network (PDN) gateway (PGW) 116, a service capabilityenablement function (SCEF) 118, a short message service (SMS) center(SMSC) 120, a gateway mobile location center (GMLC) 122, and a secureuser plane location (SUPL) location platform (SLP) 124. Exampleinterfaces for communication between the various components are alsoindicated. The architecture and individual components are given by wayof example only. One of skill in the art will recognize that aspects ofthe disclosure are applicable to communication systems with differentarchitectures and/or that implement other standards.

The SGW 114 and PGW 116 provide access to an operator's internetprotocol (IP) services 126, which may provide access to one or morethird party servers 128, such as web servers or application servers. TheSCEF 118, as will be discussed further herein, may provide one or morepower saving mode parameters or enhanced power saving mode parameters toone or more other entities to allow for timed communication to the UE102 or to allow knowledge of a current availability of the UE 102. TheSMSC 120 is configured to store, forward, convert and/or deliver SMSmessages. The SMSC 120 may include one or more of an SMS service center(SMS-SC), SMS gateway service center (SMS-GMSC), or other SMSinfrastructure or system to interface with SMS infrastructure. The GMLC122 is a control-plane system that may be used to determine or provide alocation of a UE or other mobile station. The SLP 124 is a user-planesystem that may be used to determine or provide a location of a UE orother mobile station.

In Release 12, 3GPP defined a new access stratum (AS) state referred toas power saving mode (PSM). FIG. 2 illustrates operation of the UE 102in PSM. At 202, a UE 102 sends a non-access stratum (NAS)attach/tracking area update (TAU) request message that includes a valuefor T3324 timer and a T3412 extended value (EV). At 204, an MME 110sends an NAS attach/TAU accept message, which may include a value forT3324 and T3412 to be used by the UE 102. At 206, the UE 102 releases anRRC connection with an eNB 106 or mobile network and enters an idle mode208. During the idle mode 208, the UE 102 may remain reachable throughpaging. The duration of the sojourn time in the idle mode 208 isdetermined by the T3324 timer. Upon expiry of the T3324 timer, the UE102 enters a PSM 210. The duration of the sojourn time in the PSM 210 isdetermined by the periodic TAU timer (T3412 in FIG. 2). When enteringthe PSM 210, the UE 102 turns off the AS completely and is not reachablefor MT communications. Upon expiry of the periodic TAU timer T3412, theUE 102 performs the TAU signaling procedure (described in 3GPP technicalspecification (TS) 23.401 and TS 24.301) at which time it becomesreachable for MT communications again. If the UE 102 has no pending MTcommunication or has no need for Mobile Originated (MO) communication,the network puts the UE 102 in idle mode again and may configure it fora new PSM period (if the UE 102 has indicated in the TAU request messagethat it wishes to use power saving mode).

In Release 12, PSM was designed with primarily MO traffic in mind. Whileit is possible to support MT traffic, this is done in a very inefficientway. For instance, 3GPP TS 23.682 recommends the following for supportof MT traffic:

-   -   A network side application may send an SMS or a device trigger        to trigger an application on UE to initiate communication with        the SCS/AS    -   Alternatively, if an SCS/AS has periodic downlink data, it is        more efficient when the UE initiates communication with the        SCS/AS to poll for downlink data with that period    -   For either of the options to work, the UE should request an        Active Time that is long enough to allow for potential mobile        terminated service or data delivery, e.g., to deliver an SMS

The first item above suggests using SMS-based communication, at least asan initial trigger. SMS is a store-and-forward mechanism, and thus anSMS communication can be stored by an SMS-SC until the UE 102 becomesreachable. Once the stored MT SMS is delivered to the UE 102, the lattercan initiate an MO communication with the server. One issue with thisapproach is the requirement for using SMS-based communication, whichcreates an unnecessary burden in a world of increasingly IP-basedcommunications. Another issue with SMS is that the “Active Time” (whichdesignates the duration of the idle mode sojourn time before the UE 102enters PSM, e.g., T3324 in FIG. 2) needs to be long enough to allow themobile network to indicate to the SMS-SC that the UE 102 is reachableand to allow for the delivery of the stored MT SMS to the UE 102.

The second item suggests transforming MT communication into MOcommunication using polling. While this might work well for periodic DLdata, it is highly inefficient for use cases with non-periodic MT data,as most of the time the UE 102 would poll an application server fornothing.

In Release 12, 3GPP is starting new work called FS_HLCom (3GPP TR 23.709“Study on Optimizations for High Latency Communications”). One of theuse cases under consideration is efficient support of non-scheduled(non-periodic) MT data for traffic that has some maximum delivery delayrequirement, e.g., significantly lower than typical periodic TAU timerT3412 values. This use case cannot be addressed with PSM alone asdefined in Release 12.

In TR 23.709, the solutions considered so far can be divided into twodifferent solutions. In solution 2 in TR 23.709, long-term buffering inthe SGW is proposed. In this solution, the SGW node becomes a newstore-and-forward node in the evolved packet system (EPS) user plane(U-plane). That is, the SGW would store and forward in a manner similarto the SMS-SC in the EPS control-plane (C-plane). If an MT packetarrives at the SGW while the UE 102 is in PSM, the packet is storeduntil the UE 102 comes out of PSM. In another variant of the sameproposal, the idle/PSM sojourn is replaced with an extended idle modediscontinuous reception (DRX) in which the DRX duration would be on theorder of tens of minutes. Such DRX values are not supported in Release12. One issue with long-term SGW buffering is that it can interact withend-to-end timers and retransmissions. Another issue is mobilityhandling (e.g., what happens with the stored packet if the UE 102, whilein PSM, moves to another area that is served by another SGW?).

In solution 1 and solution 3 in TR 23.709, re-using monitoring (MONTE)solutions, that are also a work in progress, are disclosed. In this setof solutions a third party application server that wishes to send MTdata needs to first subscribe for a “UE reachability” event with theEPS, either when it has pending MT data for sending or on a morelong-term basis. The EPS then informs the application server wheneverthe UE 102 exits or enters PSM by using C-plane signaling. This solutionintroduces a lot of C-plane signaling, which can be undesirable.

Another issue, common to all PSM-based solutions, is the linkage betweenPSM and the timer that triggers periodic TAU (T3412). Specifically, itis impossible to tune T3412 and PSM separately. In order to be able toserve MT traffic appropriately, the periodic TAU timer would have to beconfigured to lower values to allow the UE 102 to come out of PSM morefrequently. Unfortunately, the side effect of this would be highlyincreased power consumption because the exit from PSM requires the UE102 to execute the TAU procedure. The frequent execution of the TAUprocedure would also cause a lot of signaling load to the EPC.

In light of the above issues, Applicants disclose systems, methods anddevices for efficient support of MT communications for traffic that hasmaximum delay delivery requirements. The efficiency comes in terms ofimproved power consumption for the UE 102 and low signaling volumes forthe network. According to one embodiment, an ePSM may be defined suchthat, based on network configuration when there is no data communicationfor the UE 102, the UE 102 can alternate between successive idle modeand PSM intervals that are repeated periodically. In one embodiment, theperiod of the repetitive cycle is equal to the sum of a configured idlemode sojourn time (which may be referenced herein as Ti) plus a PSMsojourn time (which may be referenced herein as Tp). As a furtherenhancement, the repetitive pattern (Ti+Tp) may be deterministic and maybe locked on an absolute clock reference (Tref). In other words, thecombined (Ti+Tp) cycle may only start at instants defined ast=Tref+N*(Ti+Tp), where N is a whole number. In one embodiment, theparameters defining the periodic cycle (Tref, Ti, Tp) may be provided toa third party application server, or other entity, either bypre-configuration or by using the SCEF 118 to forward the information tothe application server.

If the UE 102 needs to break the cycle for any reason (e.g., initiatingMO communication, responding to paging, sending a periodic TAU, etc.),the UE 102 may return to the ePSM cycle (Ti+Tp) as soon as the networkreleases the RRC connection. Note that if the (Ti+Tp) cycle is locked toan absolute clock reference then this may involve a truncation orextension of the very first Ti or Tp interval, allowing the UE 102 tolock onto the absolute reference clock.

The devices, methods, and systems disclosed herein may have significantadvantages. For example, in embodiments where the ePSM cycle (Ti+Tp) islocked to an absolute clock reference (Tref) and the cycle parameters(Tref, Ti, Tp) are provided to the SCEF 118 or application server, theremay be no need for long-term buffering by the SGW 114 (the SGW 114 maystill need to support short-term buffering while the UE 102 is paged, asrequired according to current 3GPP specification). Thus, the third partyapplication server may always know when the UE 102 is in PSM, so it canrefrain from sending MT data at those times. In other words thebuffering may be moved from the SGW 114 to the data source (i.e., theapplication server).

As another example, contrary to Release 12, the duration of the PSMsojourn time (Tp) may not be linked to the periodic TAU timer (T3412).This may allow for configuring shorter PSM sojourn times (much shorterthan typical T3412 values), which is beneficial for serving MT trafficwithin certain delay tolerance requirements. As another example, becausethe PSM sojourn time (Tp) may not be linked to the periodic TAU timer(T3412), the UE 102 may be able to freely alternate between idle modeand PSM without any signaling with the network. This can providesignificant benefits of reducing the signaling load and improving the UE102's power efficiency.

As another example, if the ePSM cycle (Ti+Tp) is deterministic (i.e.,predictable by entities that know the cycle parameters) and is exposedto third party servers 128 (such as via an SCEF API) only a single time,there may be no need for communication with an application server everytime the UE 102 changes between being reachable and not reachable. Ofcourse, if the Ti and Tp values need to be changed for some reason, thenew values could be updated to the application server (via SCEF API).However, in some embodiments, it is not expected that Ti and Tp willchange frequently.

FIG. 3 illustrates one embodiment of a call flow for configuration of anePSM in a UE 102. At 304, the UE 102 sends a TAU request message, forexample, due to mobility or due to periodic TAU timer expiration. If theUE 102 wishes to use ePSM, it may include a set of parameters thatdescribe the desired ePSM cycle. The parameters may include one or moreof the duration of idle sojourn time (Ti), the duration of PSM sojourntime (Tp), and possibly an absolute clock reference (Tref). In oneembodiment, the absolute clock reference (Tref) is based on a clock timethat can be made available both within the UE 102 and outside the UE102, such as at an application server 302. For example, universalcoordinated time (UTC) or global positioning system (GPS) time may beused. In one embodiment, the UE 102 does not provide an absolutereference time (Tref), which may be beneficial to reduce the size of theattach/TAU request message. If the absolute reference time (Tref) is notset by the UE 102 then Tref may be selected by an MME 110, or otherdevice or entity, instead.

The MME 110 may decide whether to allow ePSM based on an operator'sconfiguration, or other requirements. If the MME 110 decides to acceptthe request, it sends, at 306, a TAU accept message including theapproved description of the ePSM cycle (i.e., the original parametervalues as proposed by the UE 102 in step 1, or modified values). Notethat the MME 110 may modify the values describing the ePSM cycle if itdoes not accept the values as proposed by the UE 102. Alternatively, Tpand Ti timer values may be configured in an HSS 112 as part of the UE102 subscription data, especially for machine-type communication (MTC)devices, and downloaded to the MME 110. If the MME 110 receives thisinformation from the HSS 112 it may use it to override the valuesrequested by the UE 102.

In one embodiment, the MME 110 may forward, at 308, the description ofthe ePSM cycle to an SCEF 118 along with a UE identifier (UE ID). At310, the application server 302 retrieves Ti, Tp, and Tref for aspecific UE ID, such as a UE ID to which the application server 302wishes to send data. For example, a third party application serverwishing to send MT data to the UE 102 registers with the SCEF 118 andobtains a description of the UE 102's ePSM cycle. Given that, in oneembodiment, the ePSM cycle is described relative to an absolute timereference (Tref), the application server 302 needs to fetch the ePSMdescription from the SCEF 118 only once. The application server 302 mayalso subscribe to be notified in case the ePSM cycle parameters aremodified or if the ePSM is cancelled for this UE 102. In one embodiment,steps 308 and 310 may be omitted.

At 312, an eNB 106 or the UE 102 releases the RRC connection. Inresponse to the RRC connection release, the UE 102 may enter the ePSMcycle by going through an idle mode first. However, note that the RRCconnection release message is asynchronous (i.e., it can occur at anyinstant), whereas the ePSM cycle, in this embodiment, is locked to anabsolute time reference. Thus, RRC release at 312 may occur eitherwithin an idle interval or within a PSM interval of an ePSM cycle. InFIG. 3 it is assumed that RRC release occurred during the PSM interval.In this case, the UE 102 can use one of the following three options. Inthe first option, the UE 102 may lock immediately to the ePSM cycle byentering PSM immediately. In this case the very first PSM interval maybe truncated.

In the second option, the UE 102 may decide to enter idle mode first andextend the idle mode until the start of the first upcoming PSM intervalof the ePSM cycle. In this case the very first idle interval is longerthan usual. This case is illustrated in FIG. 3 where the UE 102 entersan idle mode 314 upon release of the RRC connection. In the thirdoption, the UE 102 enters the idle mode 314 first and remains in theidle mode 314 for a given time duration, possibly equal to the value ofTi, before reverting to the ePSM cycle. Stated otherwise, the UE 102 maybe in an idle state for a short period before entering the PSM state,all before the first scheduled idle mode 314. Note that the second andthird options may provide a desirable benefit in that they guaranteethat the UE 102 is reachable for some time period immediately after theattach or TAU procedure, which is a time when there may be an increasedpossibility of MT signaling or data.

After entering an idle mode 316 based on an absolute reference time(Tref+N*(Ti+Tp)), the UE 102 cycles between a plurality of idle modes316, 320, 324 and a plurality of PSMs 318, 322, 326. Each idle modelasts for an idle mode duration Ti, and each PSM lasts for a PSMduration Tp. After the optional extra idle time at 314, the UE 102 maystart each idle mode at an interval defined by Tref+(N+x)*(Ti+Tp), asindicated. After the T3412 timer expires, at 328, the UE 102 sendsanother TAU request. The TAU request may include new or revisedparameter values for Ti, Tp, and/or Tref.

In one embodiment, the periodic TAU timer is independent of the ePSMcycle. Upon expiration of the periodic TAU timer (T3412), the UE 102sends a periodic TAU request message, as usual. The UE 102 may use thisopportunity to request a change of ePSM parameters or cancel the ePSM.The MME 110 may also contact the SCEF 118 to provide an updated ePSMdescription or indication that the UE 102 is not using ePSM anymore oris using modified parameters. The SCEF 118 notifies all applicationservers 302, or other entities, interested in the UE 102 about thechange.

On the other hand, if the UE 102 is happy with the current ePSMconfiguration, the UE 102 may indicate this to the MME 110 by sendingsame parameter values as at 304. In one embodiment, the UE 102 maycancel ePSM by not including any ePSM-related parameters. Note that FIG.3 provides an illustration of locking the cycle (Ti+Tp) to an absoluteclock reference (Tref). In one embodiment, if the cycle is not locked tothe absolute clock reference, the following changes would be made to thecall flow of FIG. 3: first, forwarding the ePSM parameters at 308 andproviding the parameters to the application server 302 would not occur;second, passing of the Tref parameter at 304 and 306 would not beneeded; and third, the UE 102 would immediately enter the ePSM cycle(Ti+Tp) on release of the RRC connection at 312.

In one embodiment, the signaling of ePSM parameters (i.e., Ti, Tp, Tref)in FIG. 3 also applies to the attach procedure by replacing the TAUrequest/accept messages with the attach request/accept messages.

FIG. 4 illustrates one embodiment of a call flow for MT communicationtowards a UE 102 during ePSM. At the beginning of the call flow the UE102 has entered the ePSM cycle and is alternating between the idle andPSM intervals. At 404, the application server 302 obtains the ePSM cycledescription for this UE 102, including Ti, Tp, and Tref. When theapplication server 302 has MT data for sending, it waits until the UE102 enters the idle interval before sending the MT packet(s). The UE 102goes from an idle mode 406, to a PSM mode 408, and back to an idle mode410. At 412, the application server 302 sends MT data, such as aninternet protocol (IP) packet, an SGW/PGW 402 intended for the UE 102.The application server 302 sends the MT packet at a time when the UE 102will be available to receive it (or at least be in an idle mode). TheSGW stores the MT packets in a short-term buffer, and the SGW sends, at414, a downlink data notification (DDN) message to 10 MME 110 toinitiate paging. The MME 110 triggers paging at 416. Because the UE 102is in an idle interval (the idle mode 410), the UE 102 is able toreceive and process the paging message. At 418, the UE 102 and an eNB106 establish a connection with the network and the UE 102 enters RRCconnected mode. While in the connected mode, the ePSM cycle runs inparallel, but is not used in any way. The UE 102 just tracks the ePSMcycle in the background so that it can later lock on it again. During418, the MT data may be received by the UE 102.

After the data communication is terminated, at some point the networkmay decide to release the RRC connection. The RRC connection is releasedat 420, which is within an idle interval. In the depicted embodiment,the UE 102 locks immediately on the PSM cycle at 424. As a result, thevery first idle interval is a truncated idle interval 422 because therewas not a full idle period before the PSM interval 424. Following thePSM interval 424 the UE 102 enters an idle mode 426 to continue the ePSMcycle.

Note that FIG. 4 illustrates the locking of the ePSM cycle onto anabsolute clock reference (Tref) by beginning an idle mode at somemultiple of the cycle length from Tref, by truncating an interval or byextending an interval. If no absolute clock or time reference were used,the following modifications may be made to the call flow: first,communication of ePSM configuration to the application server 302 at 404may not occur; the application server 302 may send data when it isavailable, rather than timing it for an idle interval, as at 412 (i.e.,the application server 302 would not have to wait for an idle interval,as the application server 302 would not be aware when an idle intervaloccurs for the UE 102); the SGW/PGW 402 may be required (and have thecapability) to long term buffer the packet until it is possible for theUE 102 to be paged during one of its idle intervals; and the UE 102 mayimmediately enter the ePSM cycle upon release of the RRC connection,instead of at specific intervals offset from the absolute clockreference.

In some embodiments, it may be desirable to only receive text messages,such as SMS messages, at the UE 102 when the UE 102 is not in a powersaving mode or other mode where the UE 102 is not available to receiveincoming messages or transmissions. In one embodiment, MT SMS may behandled in the same way as with Release 12 PSM. For example, if the MTSMS arrives at the MME 110 while the UE 102 is in a PSM interval, theMME 110 indicates towards the SMS infrastructure that the UE 102 isunreachable and sets the UE 102 reachability request parameter (URRP)flag. The MT SMS may be delivered when the UE 102 is brought intoconnected mode again (e.g., due to periodic TAU timer expiry or due toMO data).

However, it is also possible to streamline the MT SMS delivery byexporting the ePSM cycle (i.e., Ti, Tp, Tref) towards the SMSinfrastructure (such as an SMS-SC or SMS-GMSC). This way the SMSinfrastructure will attempt MT SMS delivery only when it knows that theUE 102 is not in the PSM interval. Examples of procedures allowing forexport of ePSM cycle towards the SMS infrastructure are discussed below.

For SMS-in-NAS option (i.e., where the MME 110 has an SGs interface withthe MSC; refer to the main body of 3GPP TS 23.272) the ePSM cycle of theUE 102 can be exported to a messaging service center (MSC) by includingit in the SGsAP-PAGING-REJECT message (see 3GPP TS 29.118 clause 8.13).The UE 102's ePSM cycle can further be exported from the MSC towards theSMS-SC by including it in the MAP-MT-FORWARD-SHORTMESSAGE responsemessage (see 3GPP TS 29.002 clause 12.9).

For SMS-in-MME option (i.e., where the MME 110 has a direct SGdinterface towards the SMS infrastructure; refer to 3GPP TS 23.272 AnnexC) the UE 102's ePSM cycle can be exported towards the SMS servicecenter by inclusion in the MT Forward Short Message answer message (3GPPTS 29.338 clause 6.2.2).

In one embodiment, information about an ePSM cycle may be forwarded tothe PGW 116 or SGW 114. For example, the PGW 116 and (more seldom) theSGW 114 may trigger a network-originated control plane procedure such asdedicated bearer modification. If the UE 102 is in the PSM interval(unavailable) when the network-originated procedure is triggered, thismay lead to timer expiry and retransmissions of general packet radioservice (GPRS) tunneling protocol control (GTP-C) messages over the S5and S11 interfaces. Note that this is a general issue with Release 12PSM and may not apply to embodiments disclosed in the presentapplication.

In one embodiment, the above issue can be addressed by exporting theePSM cycle (i.e., Ti, Tp, Tref) towards the SGW 114 and PGW 116. Forinstance, when the UE 102 performs a TAU and requests use of ePSM, theMME 110 may export the ePSM cycle to an SCEF 118 (see FIG. 3 at 308). Atthe same time, or a different time, the MME 110 may export the ePSMcycle to the SGW 114 and PGW 116 using S11 and S5 GTP-C procedures (e.g.modify bearer request).

One embodiment of an overall procedure for exporting the ePSM cycle tothe SGW 114 and PGW 116 is shown in FIG. 5. The embodiment of FIG. 5 maylook like the procedure for TAU with the addition of the ePSM cycleparameters as depicted in FIG. 5 (based on 3GPP TS 23.401 FIG.5.3.3.2-1). The call flow of FIG. 5 illustrates communication between aUE 102, an eNB 106, an RNC or BSC 502, an MME 110, an old or previousMME 504 for the UE 102, an SGW 114, a PGW 116, a poly charging and rulesfunction (PCRF) 506, and an HSS 112. At 508, a TAU procedure istriggered, such as by expiration of a timer, the UE 102 mobility, or thelike. At 510 the UE 102 sends a TAU request that includes Ti, Tp, andTref to the eNB 106. The eNB 106 sends a TAU request, with Ti, Tp, andTref, to the MME 110 at 512. At 514, the RNC or BSC 502 sends a contextrequest to the MME 110 and the MME 110 sends, at 516, a contextresponse. At 518, authentication or other security checks or proceduresare performed. At 520, the RNC or BSC 502 sends a contextacknowledgement to the MME 110. At 522, the RNC or BSC 502 sends amodify bearer request including Ti, Tp, and Tref to the SGW 114. The SGW114 sends the bearer request, with Ti, Tp, and Tref, to the PGW 116 at524. At 526, a PCEF initiated internet protocol-connectivity accessnetwork (IP-CAN) session modification is performed between the PGW 116and the PCRF 506. At 528, the PGW 116 sends a modify bearer response tothe SGW 114 and the SGW 114 sends the modify bearer response to the MME110 at 530. At 532, the RNC or BSC 502 sends an update location requestto the HSS 112. The HSS 112 sends a cancel location message to the oldMME 504 at 534, and the old MME 504 sends a cancel location acknowledgeto the HSS 112 at 536. The old MME 504 also sends an Iu release commandto the RNC or BSC 502 at 538. The RNC or BSC 502 sends an Iu releasecomplete to the old MME 504 at 540. The HSS 112 sends an update locationacknowledge to the MME 110 at 542. The MME 110 sends a TAU accept to theUE 102 at 544, and the UE 102 responds with a TAU complete message at546.

In one embodiment, it may be desirable to forward the ePSM configurationinformation to one or more location service entities. For example, ifthe location services infrastructure (such as a GMLC 122 or secure userplane location (SUPL) location platform (SLP)) initiates an MT locationrequest while the UE 102 is in the PSM interval, the location requestwill fail. Note that this is a general issue with Release 12 PSM and isnot specific to embodiments of the present application.

In one embodiment, the above issue can be addressed by exporting theePSM cycle parameters (i.e., Ti, Tp, Tref) towards the GMLC 122 (or anSLP). This will keep the GMLC 122 from attempting MT location requestsonly when it knows that the UE 102 is not in the PSM interval. FIG. 6illustrates one embodiment of general network positioning for evolvedpacket core MT location requests (EPC-MT-LR) based on 3GPP TS 23.271FIG. 9.18. Specifically, FIG. 6 illustrates a call flow between a client602, a GMLC 122, an HSS or home location register (HLR) 604, an enhancedservice mobile location center (E-SMLC) 606, an MME 110, an RAN 608(such as the E-UTRAN 104 of FIG. 1), and a UE 102.

At 610, the UE 102 enters ePSM (e.g., begins an ePSM cycle). At 612, theGMLC 122, which may not be informed that the UE 102 has entered ePSM,performs an MT location request by sending a provide subscriber locationmessage. The MME 110 determines that the UE 102 is currently in a PSMinterval and responds to the GMLC 122 at 614 by with a providesubscriber location acknowledge message, including an appropriate causevalue (“UE in ePSM”) and including the UE 102's ePSM cycle (Ti, Tp,Tref) so that the GMLC 122 can schedule future requests appropriately.At 616, the MME 110 triggers the UE 102 positioning procedure. Forexample, the MME may trigger the positioning procedure in response todetermining that the UE 102 has entered the idle interval. During thepositioning procedure, the MME 110 sends, at 618, an NAS locationnotification invoke and receives, from the UE 102, at 620, an NASlocation notification return result. The MME 110 sends a locationrequest to the E-SMLC 606 at 622. A positioning procedure occurs at 624,and the E-SMLC 606 sends a location response to the MME 110 at 626. At628, the MME 110 sends a subscriber location report message to the GMLC122 including the UE 102's current location and, optionally, includingthe UE 102's ePSM cycle parameters (Ti, Tp, Tref).

The above examples and embodiments may provide significant advantagesand benefits over the existing PSM and TAU procedures and methods. Forexample, Release 12 PSM would not be able to meet shorter deadlines(e.g., 15 minutes) except by shortening the T3412 timer, which wouldcause high power and data usage because a TAU request and procedurewould occur more frequently. In one embodiment disclosed herein, the TAUmay be decoupled from the ePSM to allow for the UE 102 to enter and exita PSM without affecting when the TAU procedures occur.

In embodiments that use the absolute clock reference (Tref), otherentities can know when the UE 102 will be reachable or unreachable. Forexample, if Tref is based on UTC or GPS time, other devices candetermine when the UE 102 is available and may only send MTcommunications when they can be received by the UE 102. This results inless control signaling, repeated sending, or other communication toreduce overall load on an EPC or mobile network. Furthermore, becauseother systems, devices, or entities know when the UE 102 is reachable,the idle or available times may be shorter, leading to a greater amountof time during which the UE 102 is in a very low power, but unreachable,mode. Also, the UE 102 can still respond to any requests within veryshort deadlines, if needed, while still having very low powerutilization. As illustrated in FIG. 3, the UE 102 may be able toalternate between idle modes and PSMs without any TAU request. In oneembodiment, the UE 102 may determine a current time during idle based ona broadcast message, such as a system information block (SIB) message.One embodiment of an SIB that may be used to help the UE 102 have anaccurate clock is an SIB16 message.

In some embodiments, the Ti, Tp cycle may not be locked to an absoluteclock reference or the absolute clock reference is not provided to otherentities (e.g., beside the MME 110 and/or UE 102). In these embodiments,the Ti, Tp cycle may still provide significant benefits because the ePSMcycle is decoupled from the TAU procedures. If there is no Tref value,the SGW 114 may buffer for a longer period of time, such as 15 minutesor more (currently SGW in Release 12 only buffers for a couple ofseconds). In one embodiment, the MME 110 tracks the Ti, Tp cycle for theUE 102 so that the UE 102 can be paged as soon as it becomes reachable.For example, the in absence of Tref the UE 102 may re-start the Ti, Tpcycle each time an RRC connection with the UE 102 is released.Similarly, the MME 110 may re-start the Ti, Tp cycle for the UE 102 eachtime the S1 release procedure with the eNB 106 is completed. Thetracking of the Ti, Tp cycle at the MME 110 will not be perfect, butcould be pretty close (e.g. 10 seconds for an idle mode would probablystill be enough time to allow the MME 110 to accurately notify the UE102 that it has incoming data).

Further example embodiments are also considered within the scope of thisdisclosure. In one embodiment, the MME 110 is configured to receive arequest from the UE 102 indicating that the UE 102 wishes to use ePSMand to configure the UE 102 for using an ePSM cycle. In one embodiment,the ePSM cycle is defined as cyclic repetition of an idle interval and aPSM interval. In one embodiment, successive occurrences of the idleintervals determine time periods during which the UE 102 is reachablefor MT communication. In one embodiment, successive occurrences of thePSM intervals determine time periods during which the UE 102 is notreachable for MT communication. In one embodiment, the MME 110 uses oneor more of an NAS message or a TAU procedure to configure the UE 102 forusing the ePSM cycle. In one embodiment, the MME 110 uses a TAU attachor NAS attach message to provide ePSM parameters or approve the UE 102to enter an ePSM cycle.

In one embodiment, the ePSM cycle is locked on an absolute timereference (e.g., Tref). In one embodiment, the MME 110 forwards adescription of the ePSM cycle to the SCEF 118. The description of theePSM cycle may or may not include one or more of Ti, Tp, or Tref. In oneembodiment, the MME 110 forwards a description of the SM cycle to SMSinfrastructure, such as an SMC, SCMS-SC, or SMS-GMSC. In one embodiment,the MME 110 forwards a description of the ePSM cycle to the SGW 114and/or the PGW 116. In one embodiment, the MME 110 forwards adescription of the ePSM cycle to the GMLC 122 or SLP.

In one embodiment, the UE 102 is configured to send a request to the MME110 indicating that it wishes to use an ePSM. The UE 102 is alsoconfigured to receive configuration parameters from the MME 110 forusing an ePSM cycle and to start using the ePSM cycle. In oneembodiment, the ePSM cycle is defined as cyclic repetition of an idleinterval and a PSM interval. In one embodiment, successive occurrencesof the idle intervals determine time periods during which the UE 102 isreachable for MT communication. In one embodiment, successiveoccurrences of the PSM intervals determine time periods during which theUE 102 is not reachable for MT communication. In one embodiment, the UE102 is configured to use NAS messaging, such as a TAU procedure toobtain ePSM configuration from the MME 110. In one embodiment, the ePSMcycle is locked on an absolute time reference (e.g., Tref).

Turning to FIG. 7, a schematic block diagram of one embodiment of a UE102 is shown. The UE 102 includes a request component 702, a decodecomponent 704, a cycle component 706, and a power mode component 708. Inone embodiment, one or more of the components 702-708 are part of aprocessor, such as a baseband processor of the UE 102. For example, abaseband processor may be sold separately and included as part of the UE102, such as a mobile phone or an MTC device. The UE 102 or processormay include logic, circuitry, code, or the like that implements each ofthe components 702-708.

The request component 702 is configured to format a request to enter apower saving mode to be sent to a mobile communications network. Forexample, the request may include one or more of the request 304 or 510discussed above. The request component 702 may send, or cause the UE 102to send, the request to use an ePSM to an MME 110 of a mobilecommunications network. In one embodiment, the request may include a TAUrequest or NAS message. In the case of a TAU request, the requestcomponent 702 may be configured to send the request in response to oneor more of expiration of a TAU timer and mobility of the UE 102. In oneembodiment, the request includes one or more of a recommended idle modetime (such as Ti), a recommended power saving mode time (such as Tp), oran absolute clock reference (Tref).

The decode component 704 is configured to decode a message from themobile communications network indicating that the wireless communicationdevice has permission to enter the power saving mode. In one embodiment,the decode component 704 is configured to decode a message from the MME110 indicating acceptance of the UE 102 to use the ePSM. For example,the message may authorize the UE 102 to enter the ePSM cycle. In oneembodiment, the decode component 704 is configured to receiveconfiguration parameters from the MME 110 comprising a time length foran idle mode and a time length for a power saving mode (e.g., Ti andTp). In one embodiment, the message from the MME 110 indicatingacceptance to use the ePSM includes configuration parameters for theePSM (e.g., Ti, Tp, and/or Tref). In one embodiment, the message fromthe mobile communications network includes the idle mode time and thepower saving mode time. In one embodiment the recommended idle time andrecommended power saving time from the UE 102 sent in a request isdifferent than the idle time and the power saving time received from themobile communications network.

The cycle component 706 is configured to determine parameters for thepower saving mode, such as the ePSM, comprising an idle mode time and apower saving mode time. In one embodiment, the cycle component 706 isfurther configured to determine configuration parameters furtherincluding an absolute time reference (such as Tref). In one embodiment,the absolute time reference includes a universal time reference based ona generally known time standard, such as a UTC time reference and/or aGPS time reference. In one embodiment, the cycle component 706 isconfigured to determine a current universal time corresponding to theuniversal time reference based on a message received during an idlemode. For example, the cycle component 706 may determine what thecurrent time is based on the received message. In one embodiment, themessage received during an idle mode comprises an SIB16 message.

The power mode component 708 is configured to cycle between the idlemode and the PSM based on the power saving mode parameters. In oneembodiment, the power mode component 708 powers down or powers upportions of a chip or the UE 102 to place the UE 102 in the idle mode orthe PSM. In one embodiment, the UE 102 is available to receivetransmissions during the idle mode and unavailable to receivetransmissions during the PSM. In one embodiment, the power modecomponent 708 may begin cycling between the idle and PSM mode uponrelease of an RRC connected mode or RRC connection with the mobilecommunications network and/or and in response to decoding a message fromthe MME 110 (or other entity of a mobile communications network)indicating acceptance for the UE 102 to use the ePSM. In one embodiment,the power mode component 708 is configured to begin cycling between theidle mode and the power saving mode based on the absolute timereference. For example, the power mode component 708 may align the idlemode or the PSM with Tref. In one embodiment, the power mode component708 is further configured to truncate or extend one of an initial idlemode time period and an initial power saving mode time period to aligncycling between the idle mode and the power saving mode with theabsolute time reference.

FIG. 8 is an example illustration of a mobile device, such as a userequipment (UE), a mobile station (MS), a mobile wireless device, amobile communication device, a tablet, a handset, or another type ofwireless communication device. The mobile device can include one or moreantennas configured to communicate with a transmission station, such asa base station (BS), an eNB, a base band unit (BBU), a remote radio head(RRH), a remote radio equipment (RRE), a relay station (RS), a radioequipment (RE), or another type of wireless wide area network (WWAN)access point. The mobile device can be configured to communicate usingat least one wireless communication standard, including 3GPP LTE, WiMAX,high speed packet access (HSPA), Bluetooth, and WiFi. The mobile devicecan communicate using separate antennas for each wireless communicationstandard or shared antennas for multiple wireless communicationstandards. The mobile device can communicate in a wireless local areanetwork (WLAN), a wireless personal area network (WPAN), and/or a WWAN.

FIG. 8 also provides an illustration of a microphone and one or morespeakers that can be used for audio input and output from the mobiledevice. The display screen may be a liquid crystal display (LCD) screenor other type of display screen, such as an organic light emitting diode(OLED) display. The display screen can be configured as a touch screen.The touch screen may use capacitive, resistive, or another type of touchscreen technology. An application processor and a graphics processor canbe coupled to internal memory to provide processing and displaycapabilities. A non-volatile memory port can also be used to providedata input/output options to a user. The non-volatile memory port mayalso be used to expand the memory capabilities of the mobile device. Akeyboard may be integrated with the mobile device or wirelesslyconnected to the mobile device to provide additional user input. Avirtual keyboard may also be provided using the touch screen.

EXAMPLES

The following examples pertain to further embodiments.

Example 1 is a UE that is configured to send a request to use an ePSM toa MME of a mobile communications network. The UE is configured toreceive configuration parameters from the MME comprising a time lengthfor an idle mode and a time length for a power saving mode. The UE isconfigured to cycle between the idle mode and the power saving modebased on the power saving mode parameters, wherein the UE is availableto receive transmissions during the idle mode and unavailable to receivetransmissions during the power saving mode.

In Example 2, the request of Example 1 includes one or more of: a TAUrequest, wherein the UE is configured to send the request in response toone or more of expiration of a TAU timer and mobility of the UE; and anattach request.

In Example 3, the configuration parameters of any of Examples 1-2further include an absolute time reference and the UE is configured tobegin cycling between the idle mode and the power saving mode based onthe absolute time reference.

In Example 4, the UE of Example 3 is further configured to truncate orextend one of an initial idle mode time period and an initial powersaving mode time period to align cycling between the idle mode and thepower saving mode with the absolute time reference

In Example 5, the UE of any of Examples 1-4 is further configured todecode a message from the MME indicating acceptance of the UE to use theePSM.

In Example 6, the message from the MME indicating acceptance in Example5 includes the configuration parameters for the ePSM.

Example 7, is a computer readable storage media storing executableinstructions that, when executed by a processor of a computer system,cause the computer system to: process a request from a UE to use anePSM; determine configuration parameters for use by the UE in the ePSM,wherein the configuration parameters include a time length for an idlemode and a time length for a power saving mode; and format a messageindicating acceptance for the UE to use the ePSM.

In Example 8, the ePSM of Example 7 includes a cyclic repetition betweenthe idle mode and the power saving mode, wherein the UE is available forMT communication in the idle mode and wherein the UE is unavailable forMT communication in the power saving mode.

In Example 9, the executable instructions of any of Examples 7-8 causethe computer system to process a request comprising a TAU request orattach request and format the message indicating acceptance comprising aTAU accept message or an attach accept message.

In Example 10, the configuration parameters of any of Examples 7-9further include a time reference based on a generally known timestandard.

In Example 11, the executable instructions of any of Examples 7-10further cause the computer system to forward at least one of theconfiguration parameters to one or more of a SCEF, a SGW, a PGW, a GMLC,and a SMS infrastructure.

In Example 12, the executable instructions of any of Examples 7-11 causethe computer system to determine the configurations parameters byreceiving the configuration parameters from a HSS for the UE.

Example 13 is a processor, such as a baseband processor, includinglogic. The logic includes a request component configured to format arequest to enter a power saving mode to be sent to a mobilecommunications network. The logic includes a decode component configuredto decode a message from the mobile communications network indicatingthat the wireless communication device has permission to enter the powersaving mode. The logic includes a cycle component configured todetermine parameters for the power saving mode comprising an idle timeand a power saving mode time. The logic includes a power mode componentconfigured to cycle between an idle mode and a power saving mode basedon the power saving mode parameters.

In Example 14, the request in Example 13 includes a recommended idletime and a recommended power saving mode time.

In Example 15, the message in Example 14 from the mobile communicationsnetwork comprises the idle time and the power saving mode time, whereinthe recommended idle time is different than the idle time and therecommended power saving time is different than the power saving time.

In Example 16, the cycle component in any of Examples 13-15 is furtherconfigured to determine parameters comprising an absolute time referencebased on a generally known time standard.

In Example 17, the absolute time reference in Example 16 includes one ormore of a UTC reference and a GPS time reference.

In Example 18, the processor of any of Examples 16-17 is configured todetermine a current time corresponding to the absolute time referencebased on a message received during an idle mode.

In Example 19, the message received during an idle mode in Example 18includes a SIB16 message.

In Example 20, the processor of any of Examples 13-19 is available toreceive or process messages during the idle mode and the processor isunavailable to receive or process messages during the power saving mode.

Example 21 is a method that includes sending, from a UE, a request touse an ePSM to a MME of a mobile communications network. The methodincludes receiving, at the UE, configuration parameters from the MMEincluding a time length for an idle mode and a time length for a powersaving mode. The method includes cycling the UE between the idle modeand the power saving mode based on the power saving mode parameters,wherein the UE is available to receive transmissions during the idlemode and unavailable to receive transmissions during the power savingmode.

In Example 22, the request in Example 21 includes one or more of: a TAUrequest, wherein sending the request comprises sending in response toone or more of expiration of a TAU timer and mobility of the UE; and anattach request.

In Example 23, the configuration parameters in any of Examples 21-22further include an absolute time reference and wherein the methodincludes beginning cycling between the idle mode and the power savingmode based on the absolute time reference.

In Example 24, the method of Example 23 further includes truncating orextending one of an initial idle mode time period and an initial powersaving mode time period to align cycling between the idle mode and thepower saving mode with the absolute time reference.

In Example 25, the method of any of Examples 21-24 further includesdecoding a message from the MME indicating acceptance of the UE to usethe ePSM.

In Example 26, the message from the MME indicating acceptance in Example25 includes the configuration parameters for the ePSM.

Example 27 is a computer implemented method for power savings. Themethod includes processing a request from a UE to use an ePSM. Themethod includes determining configuration parameters for use by the UEin the ePSM, wherein the configuration parameters include a time lengthfor an idle mode and a time length for a power saving mode. The methodincludes formatting a message indicating acceptance for the UE to usethe ePSM.

Example 28 is the computer implemented method of Example 27 wherein oneor more of: the ePSM includes a cyclic repetition between the idle modeand the power saving mode, wherein the UE is available for MTcommunication in the idle mode and wherein the UE is unavailable for MTcommunication in the power saving mode; the request comprises a trackingarea update (TAU) request or attach request and the message indicatingacceptance comprises a TAU accept message or an attach accept message;and the configuration parameters further comprise a time reference basedon a generally known time standard.

In Example 29, the executable instructions in any of Examples 27-28further cause the computer system to forward at least one of theconfiguration parameters to one or more of a SCEF, a SGW, a PGW, a GMLC,and a SMS infrastructure.

In Example 30, the executable instructions in any of Examples 27-29cause the computer system to determine the configurations parametersbased on configuration parameters received from a HSS for the UE.

Example 31 is a method that includes formatting a request to enter apower saving mode to be sent from a wireless communication device to amobile communications network. The method includes decoding a messagefrom the mobile communications network indicating that the wirelesscommunication device has permission to enter the power saving mode. Themethod includes determining parameters for the power saving modecomprising an idle time and a power saving mode time. The methodincludes cycling the wireless communication device between an idle modeand a power saving mode based on the power saving mode parameters.

Example 32 is an apparatus including means to perform a method asdisclosed or performed in any of Examples 13-31.

Example 33 is at least one computer-readable storage medium havingstored thereon computer-readable instructions, when executed, toimplement a method or realize an apparatus as in any of Examples 13-32.

Various techniques, or certain aspects or portions thereof, may take theform of program code (i.e., instructions) embodied in tangible media,such as floppy diskettes, CD-ROMs, hard drives, a non-transitorycomputer readable storage medium, or any other machine-readable storagemedium wherein, when the program code is loaded into and executed by amachine, such as a computer, the machine becomes an apparatus forpracticing the various techniques. In the case of program code executionon programmable computers, the computing device may include a processor,a storage medium readable by the processor (including volatile andnon-volatile memory and/or storage elements), at least one input device,and at least one output device. The volatile and non-volatile memoryand/or storage elements may be a RAM, an EPROM, a flash drive, anoptical drive, a magnetic hard drive, or another medium for storingelectronic data. The eNB (or other base station) and UE (or other mobilestation) may also include a transceiver component, a counter component,a processing component, and/or a clock component or timer component. Oneor more programs that may implement or utilize the various techniquesdescribed herein may use an application programming interface (API),reusable controls, and the like. Such programs may be implemented in ahigh-level procedural or an object-oriented programming language tocommunicate with a computer system. However, the program(s) may beimplemented in assembly or machine language, if desired. In any case,the language may be a compiled or an interpreted language, and combinedwith hardware implementations.

It should be understood that many of the functional units described inthis specification may be implemented as one or more components, whichis a term used to more particularly emphasize their implementationindependence. For example, a component may be implemented as a hardwarecircuit comprising custom very large scale integration (VLSI) circuitsor gate arrays, off-the-shelf semiconductors such as logic chips,transistors, or other discrete components. A component may also beimplemented in programmable hardware devices such as field programmablegate arrays, programmable array logic, programmable logic devices, orthe like.

Components may also be implemented in software for execution by varioustypes of processors. An identified component of executable code may, forinstance, comprise one or more physical or logical blocks of computerinstructions, which may, for instance, be organized as an object, aprocedure, or a function. Nevertheless, the executables of an identifiedcomponent need not be physically located together, but may comprisedisparate instructions stored in different locations that, when joinedlogically together, comprise the component and achieve the statedpurpose for the component.

Indeed, a component of executable code may be a single instruction, ormany instructions, and may even be distributed over several differentcode segments, among different programs, and across several memorydevices. Similarly, operational data may be identified and illustratedherein within components, and may be embodied in any suitable form andorganized within any suitable type of data structure. The operationaldata may be collected as a single data set, or may be distributed overdifferent locations including over different storage devices, and mayexist, at least partially, merely as electronic signals on a system ornetwork. The components may be passive or active, including agentsoperable to perform desired functions.

Reference throughout this specification to “an example” means that aparticular feature, structure, or characteristic described in connectionwith the example is included in at least one embodiment of the presentinvention. Thus, appearances of the phrase “in an example” in variousplaces throughout this specification are not necessarily all referringto the same embodiment.

As used herein, a plurality of items, structural elements, compositionalelements, and/or materials may be presented in a common list forconvenience. However, these lists should be construed as though eachmember of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as ade facto equivalent of any other member of the same list solely based onits presentation in a common group without indications to the contrary.In addition, various embodiments and examples of the present inventionmay be referred to herein along with alternatives for the variouscomponents thereof. It is understood that such embodiments, examples,and alternatives are not to be construed as de facto equivalents of oneanother, but are to be considered as separate and autonomousrepresentations of the present invention.

Although the foregoing has been described in some detail for purposes ofclarity, it will be apparent that certain changes and modifications maybe made without departing from the principles thereof. It should benoted that there are many alternative ways of implementing both theprocesses and apparatuses described herein. Accordingly, the presentembodiments are to be considered illustrative and not restrictive, andthe invention is not to be limited to the details given herein, but maybe modified within the scope and equivalents of the appended claims.

Those having skill in the art will appreciate that many changes may bemade to the details of the above-described embodiments without departingfrom the underlying principles of the invention. The scope of thepresent invention should, therefore, be determined only by the followingclaims.

1. An apparatus of a user equipment (UE) comprising: a data storagedevice configured to store data indicating an idle time lengthcorresponding to an idle mode and a power saving time lengthcorresponding to a power saving mode; and baseband circuitry operablycoupled to the data storage device and configured to: operate in anenhanced power saving mode (ePSM) comprising: the idle mode, duringwhich the UE is available to receive transmissions; and the power savingmode, during which the UE is unavailable to receive transmissions; andtransition directly from the idle mode to the power saving mode, anddirectly from the power saving mode to the idle mode in a cyclic mannerduring the ePSM based on the idle time length and the power saving timelength.
 2. The apparatus of claim 1, wherein the baseband circuitry isconfigured to enter the ePSM responsive to a release of a radio resourcecontrol (RRC) connection between the UE and a node of a cellular datanetwork.
 3. The apparatus of claim 1, wherein the ePSM starts with theidle mode and then transitions to the power saving mode.
 4. Theapparatus of claim 1, wherein a beginning of each period of the ePSM islocked to an absolute clock reference such that the beginning of eachperiod is an integer multiple of a sum of the idle time length and thepower saving time length from the absolute clock reference.
 5. Theapparatus of claim 4, wherein the absolute clock reference comprises auniversal coordinated time (UTC).
 6. The apparatus of claim 4, whereinthe absolute clock reference comprises a global positioning system (GPS)time.
 7. The apparatus of claim 1, wherein the ePSM is not locked to anabsolute clock reference.
 8. The apparatus of claim 7, wherein the ePSMis configured to enter a cycle of the ePSM immediately upon release of aradio resource control (RRC) connection.
 9. An apparatus of a userequipment (UE) comprising: wireless communication circuitry configuredto enable the UE to communicate via a cellular data network; andprocessing circuitry operably coupled to the wireless communicationcircuitry and configured to cause the wireless communication circuitryto operate in an enhanced power saving mode (ePSM) during which thewireless communication circuitry cycles back and forth between an idlemode and a power saving mode, wherein: during the idle mode the wirelesscommunication circuitry is available to receive transmissions; duringthe power saving mode the communication circuitry is unavailable toreceive transmissions; and transitions between the idle mode and thepower saving mode occur without signaling with the cellular datanetwork.
 10. The apparatus of claim 9, wherein the wirelesscommunication circuitry is configured to send a request to use the ePSMto a mobility management entity (MME) of the cellular data network. 11.The apparatus of claim 10, wherein the request includes a tracking areaupdate (TAU) request.
 12. The apparatus of claim 10, wherein the requestcomprises an attach request.
 13. The apparatus of claim 9, wherein anidle time period of the idle mode and a power saving time period of thepower saving mode are specified in a message received from a mobilitymanagement entity (MME) of the cellular data network.
 14. The apparatusof claim 13, wherein the message received from the MME comprises atracking area update (TAU) accept message.
 15. The apparatus of claim13, wherein the message received from the MME comprises an attach acceptmessage.
 16. The apparatus of claim 9, wherein communication circuitryis only available to receive text message transmissions during the idlemode.
 17. A cellular communication device comprising: a battery; and abaseband processor operably coupled to the battery and configured to:draw sufficient power from the battery to receive and processtransmissions from a cellular data network during an idle mode; drawinsufficient power from the battery to receive and process transmissionsfrom the cellular data network during a power saving mode; andtransition directly from the idle mode to the power saving mode, anddirectly from the power saving mode to the idle mode in a cyclic mannerwithout communicating with the cellular data network during an enhancedpower saving mode (ePSM).
 18. The cellular communication device of claim17, wherein the cellular communication device includes a cellulartelephone device.
 19. The cellular communication device of claim 17,wherein the cellular communication device includes amachine-type-communication (MTC) device.
 20. The cellular communicationdevice of claim 17, wherein the baseband processor includes: a requestcomponent configured to format a request to enter the ePSM; a decodecomponent configured to decode a message from the cellular data networkindicating that the cellular communication device has permission toenter the ePSM; a cycle component configured to determine an idle timecorresponding to the idle mode and a power saving time corresponding tothe power saving mode; and a power mode component configured to cyclethe between the idle mode and the power saving mode based on the idletime and the power saving time.